Enhanced transparency exoskeleton

Abstract

An increased transparency exoskeleton is provided that includes a hip joint assembly. The exoskeleton includes a hip joint assembly connecting a leg assembly to a torso portion. The hip joint assembly has a hip abduction/adduction to hip internal/external rotation to hip flexion/extension kinematic chain.

What is claimed is: 
     
         1 . An exoskeleton, comprising:
 a torso portion;   a leg assembly, the leg assembly comprising:
 a lower leg assembly comprising:
 an ankle flexion/extension joint; 
 a footbed coupled to an ankle joint, the footbed having a rear portion behind the ankle joint, the ankle joint comprising a first spherical joint and a second spherical joint; 
 an ankle actuation cable adapted to lift the rear portion of the footbed; 
 a remote parallelogram structure coupled to the ankle joint, the remote parallelogram structure allowing for yaw of the footbed and inversion/eversion of the footbed; 
 a first parallel member running from the remote parallelogram structure to the first spherical joint; and 
 a second parallel member running from the remote parallelogram structure to the second spherical joint; and 
 
 an upper leg assembly coupled to the lower leg assembly at a knee joint, the upper leg assembly comprising an ankle actuation motor to take in and release the ankle actuation cable, wherein taking in the ankle actuation cable induces planter flexion of the footbed; and 
   a hip joint assembly configured to connect the leg assembly to the torso portion, the hip joint assembly comprising a hip abduction/adduction joint comprising an actuator, the torso portion comprises a ground linkage of a four-bar linkage configured to connect the torso portion to the actuator of the hip abduction/adduction joint.   
     
     
         2 . The exoskeleton of  claim 1 , wherein the hip joint assembly defines an active hip abduction/adduction degree of freedom and an active hip flexion/extension degree of freedom. 
     
     
         3 . The exoskeleton of  claim 2 , wherein the hip joint assembly defines a passive hip internal/external rotation degree of freedom. 
     
     
         4 . The exoskeleton of  claim 1 , wherein the hip joint assembly comprises:
 the hip abduction/adduction joint defining a hip abduction/adduction axis;   a hip flexion/extension joint defining a hip flexion/extension axis;   a hip abduction/adduction actuator to drive abduction/adduction of the leg assembly about the hip abduction/adduction axis, the hip abduction/adduction actuator remote from the hip abduction/adduction axis; and   a hip flexion/extension actuator to drive flexion and extension of the leg assembly about the hip flexion/extension axis, the hip flexion/extension actuator remote from the hip flexion/extension axis.   
     
     
         5 . The exoskeleton of  claim 4 , wherein the hip joint assembly comprises:
 a scissor linkage coupled to the leg assembly; and   a hip abduction/adduction linkage coupled to the hip abduction/adduction joint, the scissor linkage and the hip abduction/adduction actuator, wherein the hip abduction/adduction actuator is adapted to drive the hip abduction/adduction linkage to induce abduction/adduction of the scissor linkage about the hip abduction/adduction axis to abduct/adduct the leg assembly.   
     
     
         6 . The exoskeleton of  claim 5 , wherein the hip abduction/adduction actuator is placed to be above a wearer's hips during use and closer to a centerline of the exoskeleton than the hip abduction/adduction axis. 
     
     
         7 . The exoskeleton of  claim 5 , wherein the hip abduction/adduction linkage is a first four-bar linkage. 
     
     
         8 . The exoskeleton of  claim 7 , wherein the scissor linkage is coupled to the hip abduction/adduction linkage by an intermediate linkage. 
     
     
         9 . The exoskeleton of  claim 8 , wherein the intermediate linkage comprises a second four-bar linkage. 
     
     
         10 . The exoskeleton of  claim 5 , wherein the scissor linkage defines a hip internal/external rotation axis for the leg assembly. 
     
     
         11 . The exoskeleton of  claim 5 , wherein the scissor linkage comprises a virtual center linkage. 
     
     
         12 . The exoskeleton of  claim 5 , wherein the hip joint assembly comprises:
 a hip flexion/extension linkage coupled to the hip flexion/extension joint, the scissor linkage, and the hip flexion/extension actuator, wherein the hip flexion/extension actuator is coupled to the leg assembly and adapted to drive the hip flexion/extension linkage to cause the leg assembly to flex/extend about the hip flexion/extension axis.   
     
     
         13 . The exoskeleton of  claim 12 , wherein the hip flexion/extension linkage is a four-bar linkage. 
     
     
         14 . The exoskeleton of  claim 12 , wherein the scissor linkage is coupled to the hip flexion/extension linkage by an intermediate linkage. 
     
     
         15 . The exoskeleton of  claim 14 , wherein the intermediate linkage is a second four-bar linkage. 
     
     
         16 . The exoskeleton of  claim 12 , wherein the scissor linkage is coupled to the hip abduction/adduction linkage by a first intermediate linkage and to the hip flexion/extension linkage by a second intermediate linkage, wherein the hip abduction/adduction linkage is a first four-bar linkage, the first intermediate linkage is a second four bar linkage, the hip flexion/extension linkage is a third four-bar linkage, and the second intermediate linkage is a fourth four-bar linkage. 
     
     
         17 . The exoskeleton of  claim 1 , wherein the lower leg assembly comprises a support structure adapted to remain in place relative to a wearer's leg when the exoskeleton is worn and wherein the remote parallelogram structure comprises:
 a first cross member coupled to the first parallel member, the second parallel member, and the support structure; and   a second cross member parallel to the first cross member, the second cross member coupled to the first parallel member, the second parallel member, and the support structure.   
     
     
         18 . The exoskeleton of  claim 17 , wherein the first cross member is coupled to the first parallel member at first pin joint, the support structure at a third spherical joint, and the second parallel member at a second pin joint and wherein the second cross member is coupled to the first parallel member at a third pin, the support structure at a fourth spherical joint and the second parallel member at a fourth pin joint. 
     
     
         19 . The exoskeleton of  claim 1 , further comprising a biasing member coupled to the first parallel member and the footbed to bias the rear portion of the footbed down. 
     
     
         20 . The exoskeleton of  claim 1 , wherein the footbed comprises a first clevis for the first spherical joint and a second clevis for the second spherical joint, wherein the first clevis and the second clevis have a tapered profile to limit a range of motion of the footbed. 
     
     
         21 . The exoskeleton of  claim 1 , further comprising a load sensor disposed to sense a load indicative of tension in the ankle actuation cable. 
     
     
         22 . The exoskeleton of  claim 1 , wherein the exoskeleton is a load bearing exoskeleton. 
     
     
         23 . An exoskeleton, comprising:
 a torso portion;   a leg assembly, comprising:
 a lower leg assembly, comprising:
 an ankle flexion/extension joint; 
 a footbed coupled to an ankle joint, the footbed having a rear portion behind the ankle joint; 
 an ankle actuation cable adapted to lift the rear portion of the footbed; and 
 an upper leg assembly coupled to the lower leg assembly at a knee joint, the upper leg assembly comprising an ankle actuation motor to take in and release the ankle actuation cable, wherein taking in ankle actuation cable induces planter flexion of the footbed, the lower leg assembly comprising a remote parallelogram structure coupled to the ankle joint, the remote parallelogram structure allowing for yaw of the footbed and inversion/eversion of the footbed; and 
 
 a hip joint assembly connecting the leg assembly to the torso portion, the hip joint assembly comprising a hip abduction/adduction to hip internal/external rotation to hip flexion/extension kinematic chain; 
   wherein the ankle joint comprises a first spherical joint and a second spherical joint and wherein the lower leg assembly further comprises a first parallel member running from the remote parallelogram structure to the first spherical joint and a second parallel member running from the remote parallelogram structure to the second spherical joint.   
     
     
         24 . The exoskeleton of  claim 23 , wherein the hip joint assembly comprises:
 the hip abduction/adduction joint defining a hip abduction/adduction axis;   a hip flexion/extension joint defining a hip flexion/extension axis;   a hip abduction/adduction actuator to drive abduction/adduction of the leg assembly about the hip abduction/adduction axis, the hip abduction/adduction actuator remote from the hip abduction/adduction axis; and   a hip flexion/extension actuator to drive flexion and extension of the leg assembly about the hip flexion/extension axis, the hip flexion/extension actuator remote from the hip flexion/extension axis.   
     
     
         25 . The exoskeleton of  claim 24 , wherein the hip joint assembly comprises:
 a scissor linkage coupled to the leg assembly; and   a hip abduction/adduction linkage coupled to the hip abduction/adduction joint, the scissor linkage and the hip abduction/adduction actuator, wherein the hip abduction/adduction actuator is adapted to drive the hip abduction/adduction linkage to induce abduction/adduction of the scissor linkage about the hip abduction/adduction axis to abduct/adduct the leg assembly.   
     
     
         26 . The exoskeleton of  claim 23 , further comprising a biasing member coupled to the first parallel member and the footbed to bias the rear portion of the footbed down.